206660666 has 16 divisors (see below), whose sum is σ = 318441024. Its totient is φ = 100532544.

The previous prime is 206660659. The next prime is 206660669. The reversal of 206660666 is 666066602.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (206660669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18050 + ... + 27186.

It is an arithmetic number, because the mean of its divisors is an integer number (19902564).

Almost surely, 2^206660666 is an apocalyptic number.

206660666 is a deficient number, since it is larger than the sum of its proper divisors (111780358).

206660666 is a wasteful number, since it uses less digits than its factorization.

206660666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9445.

The product of its (nonzero) digits is 93312, while the sum is 38.

The square root of 206660666 is about 14375.6970613602. The cubic root of 206660666 is about 591.2247525897.

The spelling of 206660666 in words is "two hundred six million, six hundred sixty thousand, six hundred sixty-six".